It is known that silent discharge occurs upon disposing a dielectric between two electrodes and applying a high alternating current voltage or a periodic pulsed voltage between the electrodes. In the resulting plasma field, active species, radicals, and ions are produced to promote a reaction and decomposition of gas. This phenomenon may be utilized to remove toxic components contained in engine exhaust gas or various kinds of incinerator exhaust gas.
For example, a plasma reactor which treats NOx, carbon particulate, HC, and CO contained in engine exhaust gas or incinerator exhaust gas by passing the engine exhaust gas or various kinds of incinerator exhaust gas through a plasma field has been disclosed (e.g. JP-A-2001-164925).